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what system is the spinal cord and brain in what system is the brain spinal cord and nerves part of what system includes the spinal cord brain and nerves what part of the nervous system is the spinal cord and brain what is the spinal cord and brain what system is the brain and spinal cord part of what protects the spinal cord and brain what connects the spinal cord and brain what surrounds the spinal cord and brain what covers the spinal cord and brain
